View source for Q code

The '''Q-code''' is a standardized collection of three-letter codes that each start with the letter "Q". It is an [[Operating signals|operating signal]] initially developed for commercial [[radiotelegraphy|radiotelegraph]] communication and later adopted by other radio services, especially [[amateur radio]]. To distinguish the use of a Q-code transmitted as a question from the same Q-code transmitted as a statement, operators either prefixed it with the military network question marker {{overline|INT}} or suffixed it with the standard Morse question mark {{overline|UD}}.

Although Q-codes were created when radio used [[Morse code]] exclusively, they continued to be employed after the introduction of voice transmissions. To avoid confusion, transmitter [[call sign]]s are restricted; countries can be issued unused Q-Codes as their [[ITU prefix]] e.g. [[List of ITU letter codes|Qatar is QAT]].

Codes in the range QAA–QNZ are reserved for aeronautical use; QOA–QQZ for maritime use and QRA–QUZ for all services.

"Q" has no official meaning, but it is sometimes assigned a word with [[mnemonic]] value, such as "question" or "query", for example in QFE: "query field elevation".<ref>{{cite web |url=http://www.boeing.com/commercial/aeromagazine/aero_16/polar_story.html |title=Aero 16 – Polar Route Operations|first=277808-Elizabeth A. |last=Franklin |access-date=5 September 2016 |url-status=dead |archive-url=https://web.archive.org/web/20011113093037/https://www.boeing.com/commercial/aeromagazine/aero_16/polar_story.html |archive-date=13 November 2001}}</ref>

==Early development==
The original Q-codes were created, ''circa'' 1909, by the British government as a "List of abbreviations ... prepared for the use of British ships and coast stations licensed by the [[Postmaster General of the United Kingdom|Postmaster General]]".<ref>{{cite book |last=Great Britain|first=Post Office|date=October 1909|title=Handbook for wireless telegraph operators working installations licensed by His Majesty's postmaster-general|oclc=40616664|location=London|publisher=His Majesty's Stationery Office|at=appendix iii}}</ref> The Q-codes facilitated communication between maritime radio operators speaking different languages, so they were soon adopted internationally. A total of forty-five Q-codes appeared in the "List of Abbreviations to be used in Radio Communications", which was included in the Service Regulations affixed to the [[International Radiotelegraph Convention (1912)|Second International Radiotelegraph Convention in London]] (The convention was signed on July 5, 1912, and became effective July 1, 1913.)

The following table reviews a sample of the all-services Q-codes adopted by the 1912 convention:
{| class="wikitable plainrowheaders" summary="First 12&nbsp;Q-codes listed in the<br/>1912 International Radiotelegraph Convention, including meaning and sample use"
|+ First twelve Q-codes listed in the 1912 International Radiotelegraph Convention Regulations
|-
!scope="col"| Code
!scope="col"| Question
!scope="col"| Answer or notice
|-
!scope="row"| '''QRA'''
| What ship or coast station is that?
| This is ____.
|-
!scope="row"| '''QRB'''
| What is your distance?
| My distance is ____.
|-
!scope="row"| '''QRC'''
| What is your true bearing?
| My true bearing is ____ degrees.
|-
!scope="row"| '''QRD'''
| Where are you bound for?
| I am bound for ____.
|-
!scope="row"| '''QRF'''
| Where are you bound from?
| I am bound from ____.
|-
!scope="row"| '''QRG'''
| What line do you belong to?
| I belong to the ____ Line.
|-
!scope="row"| '''QRH'''
| What is your wavelength in meters? 
| My wavelength is ____ meters.
|-
!scope="row"| '''QRJ'''
| How many words have you to send? 
| I have ____ words to send.
|-
!scope="row"| '''QRK'''
| How do you receive me? 
| I am receiving (1–5).<br>''(1) is unreadable and (5) is perfect.''
|-
!scope="row"| '''QRL'''
| Are you busy?
| I am busy.
|-
!scope="row"| '''QRM'''
| Are you being interfered with? 
| I am being interfered with.
|-
!scope="row"| '''QRN'''
| Are the [[Radio atmospherics|atmospherics]] strong? 
| Atmospherics (noise) are very strong.
|}

==Later use==
Over the years the original Q-codes were modified to reflect changes in radio practice. For example, QSW / QSX originally stood for, "Shall I increase / decrease my spark frequency?", but in the 1920s [[spark-gap transmitter]]s were gradually being banned from land stations, making that meaning obsolete.<ref>{{Cite web|url=https://books.google.com/books?id=sEeaJC_y22EC&q=spark&pg=PA14-IA15|title=Contact at Sea: A History of Maritime Radio Communications|first=Peter B.|last=Schroeder|date=December 29, 1967|publisher=Ardent Media|via=Google Books}}</ref> By the 1970s, the ''Post Office Handbook for Radio Operators'' listed over a hundred Q-codes,covering a wide range of subjects including radio procedures, meteorology, radio direction finding, and search and rescue.

Some Q-codes are also used in [[aviation]], in particular QNE, QNH and QFE, referring to certain [[altimeter setting]]s. These codes are used in radiotelephone conversations with [[air traffic control]] as unambiguous shorthand, where safety and efficiency are of vital importance. A subset of Q-codes is used by the [[Miami-Dade County, Florida]] local government for law enforcement and fire rescue communications, one of the few instances where Q-codes are used in ground voice communication.<ref>{{cite magazine |magazine=National Communications Magazine |url=http://bearcat1.com/radiofl.htm |title=Radio codes & signals – Florida |access-date=2010-01-30}}</ref>

The QAA–QNZ code range includes phrases applicable primarily to the aeronautical service,<ref>{{cite web |url=http://www.airwaysmuseum.com/Q%20code.htm |title=The Q-Code |access-date=5 September 2016}}</ref> as defined by the [[International Civil Aviation Organization]].<ref>{{cite book |publisher=[[ICAO]] |series=Procedures for Air Navigation Services (PANS) |id=Doc 8400 |title=The ICAO Q-Code}}</ref> The QOA–QQZ code range is reserved for the maritime service.  The QRA–QUZ code range includes phrases applicable to all services and is allocated to the [[International Telecommunication Union]].<ref>{{cite web |url=http://www.globalsecurity.org/military/library/policy/navy/nrtc/14244_ch4.pdf |title=SM |access-date=2016-09-06}}</ref> QVA–QZZ are not allocated.<ref>{{cite web |url=http://www.portland-amateur-radio-club.org.uk/resources/q-codes.pdf |title=portland-amateur-radio-club.org.uk |access-date=5 September 2016 |url-status=dead |archive-url=https://web.archive.org/web/20111006210352/http://www.portland-amateur-radio-club.org.uk/resources/q-codes.pdf |archive-date=6 October 2011}}</ref> Many codes have no immediate applicability outside one individual service, such as maritime operation (many QO or QU series codes) or [[radioteletype]] operation (the QJ series).<ref>{{cite web |url=http://kyalami.homeip.net/qcodes.htm |title=Q-Codes |access-date=2009-03-20 |archive-url=https://web.archive.org/web/20090323113250/http://kyalami.homeip.net/qcodes.htm |archive-date=2009-03-23 |url-status=dead }}</ref>

Many military and other organisations that use Morse code have adopted additional codes, including the [[Z code]] used by most European and [[NATO]] countries. The Z code adds commands and questions adapted for military radio transmissions, for example, "ZBW 2", which means "change to backup frequency number 2", and "ZNB abc", which means "my checksum is abc, what is yours?"<ref>{{cite web |url=http://www.armymars.net/ArmyMARS/DigitalOps/Resources/acp131-operating-sigs.pdf |id=ACP 131(E) |archive-url=https://web.archive.org/web/20111119091213/http://www.armymars.net/ArmyMARS/DigitalOps/Resources/acp131-operating-sigs.pdf |archive-date=2011-11-19 |series=Communications Instructions |title=Operating Signals |date=March 1997 |url-status=usurped |quote=Chapter&nbsp;2 contains a full list of 'Q' codes}}</ref>

Used in their formal question / answer sense, the meaning of a Q-code varies depending on whether the individual Q-code is sent as a question or an answer. For example, the message "QRP?" means "Shall I decrease transmitter power?", and a reply of "QRP" means "Yes, decrease your transmitter power", whereas an unprompted statement "QRP" means "Please decrease your transmitter power". This structured use of Q-codes is fairly rare and now mainly limited to amateur radio and military [[Morse code]] (CW) traffic networks.

==Listing according to service==
*QAA to QNZ – Assigned by the [[International Civil Aviation Organization]] (ICAO).
*QNA to QNZ – The [[American Radio Relay League]] (ARRL) has also developed its own [[QN Signals]] for message handling located in this range. Even though they overlap with other signals, the ARRL determined that their exclusive use in [[National Traffic System|NTS]] nets limits confusion.
*QOA to QQZ – For the [[Maritime Mobile Service Q Codes|Maritime Mobile Service]].
*QRA to QUZ – Assigned by the International Telecommunication Union Radiocommunication Sector ([[ITU-R]]).

===Aeronautical Code signals (QAA–QNZ; ICAO)===
{{Main|Aeronautical Code signals}}

First defined in ICAO publication "Doc 6100-COM/504/1" and in "ICAO Procedures for Air Navigation Services, Abbreviations and Codes (PANS-ABC)" [Doc8400-4] (4th edition 1989), the majority of the Q-codes have fallen out of common use; for example today reports such as QAU ("I am about to jettison fuel") and QAZ ("I am flying in a storm") would be voice or computerised transmissions. But several remain part of the standard [[ICAO]] radiotelephony phraseology in aviation. These are also part of [[ACP-131|ACP131]], which lists all ITU-R Q-codes, without grouping them by aeronautical/marine/general use.<ref>{{cite web|title=List of Q-codes|url=http://www.kloth.net/radio/qcodes.php}}</ref>

{| class="wikitable"
|-
! 
!Question?
!Answer or advice
|-
|'''QAB '''
|May I have clearance (for ____) from ____ (''place'') to ____ (''place'') at flight level/altitude ____ ?
|You are cleared (''or'' ____ is cleared) by ____ from ____ (''place'') to ____ (''place'') at flight level/altitude ____.
|-
|'''QAF '''
|Will you advise me when you are (were) at (over) ____ (''place'')? 
|I am (was) at (over) ____ (''place'') (at ____ hours) at flight level / altitude ____.
|-
|'''QAG '''
| 
|Arrange your flight in order to arrive over ____ (''place'') at ____ hours. <br/>
''or''<br/> I am arranging my flight in order to arrive over ____ (''place'') at ____ hours. 
|-
|'''QAH '''
|What is your height above ____ (''datum'')? 
|I am at ____ flight level / altitude ____.<br/>
''or''<br/>
Arrange your flight so as to reach flight level / altitude ____ at ____ (''hours or place''). 
|-
|'''QAI '''
|What is the essential traffic respecting my aircraft? 
|The essential traffic respecting your aircraft is ____. 
|-
|'''QAK '''
|Is there any risk of collision? 
|There is risk of collision. 
|-
|'''QAL '''
|Are you going to land at ____ (''place'')? <br/>
''or''<br/> Has aircraft ____ landed at ____ (''place'')? 
|I am going to land at ____ (''place''). <br/>
''or''<br/> (You may) land at ____ (''place''). <br/>
''or''<br/> Aircraft ____ landed at ____ (''place''). 
|-
|'''QAM '''
|What is the latest available meteorological observation for ____ (''place'')? 
|Meteorological observation made at ____ (''place'') at ____ hours was as follows ____.{{efn|The information in response to '''QAM?''' may be given in Q-code form or [[METAR]] format.}} 
|-
|'''QAN '''
|What is the surface wind direction and speed at ____ (''place'')? 
|The surface wind direction and speed at ____ (''place'') at ____ hours is ____ (''direction'') ____ (''speed''). 
|-
|'''QAO '''
|What is the wind direction in degrees TRUE and speed at ____ (''position or zone/s'') at each of the ____ (''figures'') ____ (''units'') levels above ____ (''datum'')? 
|The wind direction and speed at (''position or zone/s'') at flight level/altitude ____ is:<br/> ____ (vertical distance) ____ degrees TRUE ____ (''speed''). 
|-
|'''QAP '''
|Shall I listen for you (''or'' for ____) on ____ kHz (____ MHz)? 
|Listen for me (''or'' for ____) on ____ kHz (____ MHz). 
|-
|'''QAQ '''
|Am I near a prohibited, restricted, or danger area?<br/>
''or''<br/> Am I near area ____ (''identification of area'')? 
|You are ____ (''number'') area ____ (''identification of area'').<br/> 1. near<br/> 2. flying within
|-
|'''QAR '''
|May I stop listening on the watch frequency for ____ minutes? 
|You may stop listening on the watch frequency for ____ minutes. 
|-
|'''QAU '''
|Where may I jettison fuel? 
|I am about to jettison fuel.<br/>
''or''<br/> Jettison fuel in ____ (''area''). 
|-
|'''QAW '''
| 
|I am about to carry out overshoot procedure. 
|-
|'''QAY '''
|Will you advise me when you pass (passed) ____ (''place'') bearing 090 (270) degrees relative to your heading? 
|I passed ____ (''place'') bearing ____ degrees relative to my heading at ____ hours. 
|-
|'''QAZ '''
|Are you experiencing communication difficulties through flying in a storm? 
|I am experiencing communication difficulties through flying in a storm. 
|-
|'''QBA '''
|What is the horizontal visibility at ____ (''place'')? 
|The horizontal visibility at ____ (''place'') at ____ hours is ____ (''distance figures and units''). 
|-
|'''QBB '''
|What is the amount, type and height above official aerodrome elevation of the base of the cloud [at ____ (''place'')]? 
|The amount, type and height above official aerodrome elevation of the base of the cloud at ____ (''place'') at ____ hours is:<br/> ____ eights (____ type) at ____ (''figures and units'') height above official aerodrome elevation. 
|-
|'''QBC '''
|Report meteorological conditions as observed from your aircraft [at ____ (''position or zone'')] [(at ____ hours)]. 
|The meteorological conditions as observed from my aircraft at ____ (''position or zone'') at ____ hours at ____ (''figures and units'') height above ____ (''datum'') are ____.{{efn|The answer to '''QBC''' is required to be an [[AIREP]] format message.}}
|-
|'''QBD '''
|How much fuel have you remaining (''expressed as hours and/or minutes of consumption'')? 
|My fuel will endure for ____ (''hours and/or minutes''). 
|-
|'''QBE '''
| 
|I am about to wind in my aerial. 
|-
|'''QBF '''
|Are you flying in cloud? 
|I am flying in cloud at ____ flight level/altitude ____ [and I am ascending (descending) to flight level/altitude ____]. 
|-
|'''QBG '''
|Are you flying above cloud? 
|I am flying above cloud and at flight level/altitude ____.<br/>
''or''<br/> Maintain a vertical distance of ____ (''figures and units'') above clouds, smoke, haze or fog levels. 
|-
|'''QBH '''
|Are you flying below cloud? 
|I am flying below cloud and at flight level/altitude ____.<br/>
''or''<br/> Maintain a vertical distance of ____ (''figures and units'') below cloud. 
|-
|'''QBI '''
|Is flight under IFR compulsory at ____ (''place'') [''or'' from ____ to ____ (''place'')]? 
|Flight under IFR is compulsory at ____ (''place'') [''or'' from ____ to ____ (''place'')]. 
|-
|'''QBJ '''
|What is the amount, type and height above ____ (''datum'') of the top of the cloud [at ____ (''position or zone'')]? 
|At ____ hours at ____ (''position or zone'') the top of the cloud is:<br/> amount ____ eights (____ type) at ____ (''figures and units'') height above ____ (''datum''). 
|-
|'''QBK '''
|Are you flying with no cloud in your vicinity? 
|I am flying with no cloud in my vicinity and at flight level/altitude ____.
|-
|'''QBM '''
|Has ____ sent any messages for me? 
|Here is the message sent by ____ at ____ hours. 
|-
|'''QBN '''
|Are you flying between two layers of cloud? 
|I am flying between two layers of cloud and at flight level / altitude ____.
|-
|'''QBO '''
|What is the nearest aerodrome at which flight under VFR is permissible and which would be suitable for my landing? 
|Flying under VFR is permissible at ____ (''place'') which would be suitable for your landing. 
|-
|'''QBP '''
|Are you flying in and out of cloud? 
|I am flying in and out of cloud and at flight level/altitude ____.
|-
|'''QBS '''
| 
|Ascend (''or'' descend) to ____ (''figures and units'') height above ____ (''datum'') before encountering instrument meteorological conditions or if visibility falls below ____ (''distance figures and units'') and advise. 
|-
|'''QBT '''
|What is the runway visual range at ____ (''place'')? 
|The runway visual range at ____ (''place'') at ____ hours is ____ (''distance figures and units''). 
|-
|'''QBV '''
|Have you reached flight level/altitude ____ [''or'' ____ (''area or place'')]? 
|I have reached ____ flight level/altitude ____ [''or'' ____ (''area or place'')].<br/>
''or''<br/>
Report reaching flight level/altitude ____ [''or'' ____ (''area or place'')]. 
|-
|'''QBX '''
|Have you left ____ flight level/altitude ____ [''or'' ____ (''area or place'')]? 
|I have left ____ flight level/altitude ____ [''or'' ____ (''area or place'')].<br/>
''or''<br/>
Report leaving flight level/altitude ____ [''or'' ____ (''area or place'')]. 
|-
|'''QBZ '''
|Report your flying conditions in relation to clouds. 
|''The reply to'' QBZ ? ''is given by the appropriate answer form of signals'' QBF, QBG, QBH, QBK, QBN ''and'' QBP.
|-
|'''QCA '''
|May I change my flight level/altitude from ____ to ____ ?
|You may change your flight level/altitude from ____ to ____<br/>
''or''<br/>
I am changing my flight level/altitude from ____ to ____.
|-
|'''QCB '''
| 
|Delay is being caused by ____.<br/> 1. you're transmitting out of turn.<br/> 2. your slowness in answering.<br/> 3. lack of your reply to my ____.
|-
|'''QCE '''
|When may I expect approach clearance? 
|Expect approach clearance at ____ hours.<br/>
''or''<br/> No delay expected. 
|-
|'''QCF '''
| 
|Delay indefinite. Expect approach clearance not later than ____ hours.
|-
|'''QCH '''
|May I taxi to ____ (''place'')? 
|Cleared to taxi to ____ (''place'').
|-
|'''QCI '''
| 
|Make a 360-degree turn immediately (turning to the ____).<br/>
''or''<br/>
I am making a 360-degree turn immediately (turning to the ____). 
|-
|'''QCS '''
| 
|My reception on ____ frequency has broken down. 
|-
|'''QCX '''
|What is your full call sign? 
|My full call sign is ____ .<br/>
''or''<br/> Use your full call sign until further notice.
|-
|'''QCY '''
| 
|I am working on a trailing aerial.<br/>
''or''<br/> Work on a trailing aerial.
|-
|'''QDB '''
|Have you sent message ____ to ____ ?
|I have sent message ____ to ____.
|-
|'''QDF '''
|What is your D-Value at ____ (''position'')? <br/>
''or''<br/> What is the D-Value at ____ (''place or position'') (at ____ hours) for the ____ millibar level?
|My D-Value at ____ (''position'') at ____ (''figures and units'') height above the 1013.2 millibars datum is ____ (''D-Value figures and units'') ____ (''specify plus or minus'').<br/>
''or''<br/>
The D-Value at ____ (''place or position'') at ____ hours for the ____ millibar level is (''D-Value figures and units'') ____ (''specify plus or minus'').{{efn|When responding to '''QDF''' if the true altitude (radio altitude) is greater than the pressure altitude '''PS''' (Plus) is used and when it is less '''MS''' (Minus) is used.}}
|-
|'''QDL '''
|Do you intend to ask me for a series of bearings? 
|I intend to ask you for a series of bearings.
|-
|'''QDM '''
|Will you indicate the '''''magnetic''''' heading for me to steer towards you (''or'' ____) with no wind? 
|The '''''magnetic''''' heading for you to steer to reach me (''or'' ____) with no wind was ____ degrees (at ____ hours).
|-
|'''QDP '''
|Will you accept control (''or'' responsibility) of (for) ____ now (''or'' at ____ hours)? 
|I will accept control (''or'' responsibility) of (for) ____ now (''or'' at ____ hours).
|-
|'''QDR '''
|What is my '''''magnetic''''' bearing from you (''or'' from ____)? 
|Your '''''magnetic''''' bearing from me (''or'' from ____) was ____ degrees (at ____ hours).
|-
|'''QDT '''
|Are you flying in visual meteorological condition? 
|I am flying in visual meteorological condition.<br/>
''or''<br/>
You are cleared subject to maintaining own separation and visual meteorological conditions.
|-
|'''QDU '''
| 
|Cancelling my [[IFR]] flight.<br/>
''or''<br/>
[[IFR]] flight cancelled at ____ (''time'').
|-
|'''QDV '''
|Are you flying in a flight visibility of less than ____ (''figures and units'')? 
|I am flying in a flight visibility of less than ____ (''figures and units'') at flight level/altitude ____
|-
|'''QEA '''
|May I cross the runway ahead of me? 
|You may cross the runway ahead of you.
|-
|'''QEB '''
|May I turn at the intersection? 
|Taxi as follows at the intersection ____.<br/> (straight ahead DRT<br/> turn left LEFT<br/> turn right RIGHT). 
|-
|'''QEC '''
|May I make a 180-degree turn and return down the runway? 
|You may make a 180-degree turn and return down the runway.
|-
|'''QED '''
|Shall I follow the pilot vehicle? 
|Follow the pilot vehicle.
|-
|'''QEF '''
|Have I reached my parking area? <br/>
''or''<br/> Have you reached your parking area? 
|You have reached your parking area.<br/>
''or''<br/> I have reached my parking area.
|-
|'''QEG '''
|May I leave the parking area? <br/>
''or''<br/> Have you left the parking area? 
|You may leave the parking area.<br/>
''or''<br/> I have left the parking area.
|-
|'''QEH '''
|May I move to the holding position for runway number ____ ? <br/>
''or''<br/> Have you moved to the holding position for runway number ____ ? 
|Cleared to the holding position for runway number ____ <br/>
''or''<br/> I have moved to the holding position for runway number ____.
|-
|'''QEJ '''
|May I assume position for take-off? <br/>
''or''<br/> Have you assumed position for take-off? 
|Cleared to hold at take-off position for runway number ____.<br/>
''or''<br/> I am assuming take-off position for runway number ____ and am holding. 
|-
|'''QEK '''
|Are you ready for immediate take-off? 
|I am ready for immediate take-off. 
|-
|'''QEL '''
|May I take-off (and make a ____ hand turn after take-off)? 
|You are cleared to take-off (turn as follows after take-off ____). 
|-
|'''QEM '''
|What is the condition of the landing surface at ____ (''place'')? 
|The condition of the landing surface at ____ (''place'') is ____.{{efn|The format for response to '''QEM''' is sent as appropriate [[NOTAM]] code groups.}}
|-
|'''QEN '''
|Shall I hold my position? 
|Hold your position 
|-
|'''QEO '''
|Shall I clear the runway (''or'' landing area)? <br/>
''or''<br/> Have you cleared the runway (''or'' landing area)? 
|Clear the runway (''or'' landing area).<br/>
''or''<br/> I have cleared the runway (''or'' landing area).
|-
|'''QES '''
|Is a right-hand circuit in force at ____ (''place'')? 
|A right-hand circuit is in force at ____ (''place''). 
|-
|'''QFA '''
|What is the meteorological forecast for ____ (''flight, route, section of route or zone'') for the period ____ hours until ____ hours? 
|The meteorological forecast for ____ (''flight, route, section of route or zone'') for the period ____ hours until ____ hours is ____.
|-
|'''QFB '''
| 
|The ____<br/> 1) approach<br/> 2) runway<br/> 3) approach and runway<br/> lights are out of order.
|-
|'''QFC '''
|What is the amount, the type and the height above ____ (''datum'') of the base of the cloud at ____ (''place, position or zone'')? 
|At ____ (''place, position or zone'') the base of the cloud is ____ eighths ____ type at ____ (''figures and units'') height above ____ (''datum'').
|-
|'''QFD '''
|1. Is the ____ visual beacon [at ____ (''place'')] in operation?<br/> 2. Will you switch on the ____ visual beacon [at ____ (''place'')]?<br/> 3. Will you extinguish the aerodrome visual beacon [at ____ (''place'')] until I have landed? 
|1. The ____ visual beacon [at ____ (''place'')] is in operation<br/> 2. I will extinguish the aerodrome visual beacon [at ____ (''place'')] until your landing is completed.
|-
|'''QFE '''
|What should I set on the subscale of my altimeter so that the instrument would indicate its height above the reference elevation being used? 
|If you set the subscale of your altimeter to read ____ millibars, the instrument would indicate its height above aerodrome elevation (above threshold, runway number ____).
|-
|'''QFF '''
|[At ____ (''place'')] what is the present atmospheric pressure converted to mean sea level in accordance with meteorological practice? 
|At ____ (''place'') the atmospheric pressure converted to mean sea level in accordance with meteorological practice is (''or'' was determined at ____ hours to be) ____ millibars. 
|-
|'''QFG '''
|Am I overhead? 
|You are overhead.
|-
|'''QFH '''
|May I descend below the clouds? 
|You may descend below the clouds.
|-
|'''QFI '''
|Are the aerodrome lights lit? 
|The aerodrome lights are lit. <br/>
''or''<br/> Please light the aerodrome lights.
|-
|'''QFL '''
|Will you send up pyrotechnical lights? 
|I will send up pyrotechnical lights.
|-
|'''QFM '''
|What flight level/altitude ____.<br/> 1. should I maintain?<br/> 2. are you maintaining?<br/> 3. do you intend cruising at? 
|____  ____.<br/>
1. Maintain (''or'' fly at) flight level / altitude ____.<br/> 2. I am maintaining flight level / altitude ____ <br/> 3. I intend cruising at flight level/altitude ____.
|-
|'''QFO '''
|May I land immediately? 
|You may land immediately.
|-
|'''QFP '''
|Will you give me the latest information concerning ____ facility [at ____ (''place'')]? 
|The latest information concerning ____ facility [at ____ (''place'')] is as follows ____.{{efn|The response format to '''QFP''' is sent using appropriate [[NOTAM]] code groups.}}
|-
|'''QFQ '''
|Are the approach and runway lights lit? 
|The approach and runway lights are lit. <br/>
''or''<br/> Please light the approach and runway lights.
|-
|'''QFR '''
|Does my landing gear appear damaged? 
|Your landing gear appears damaged.
|-
|'''QFS '''
|Is the radio facility at ____ (''place'') in operation? 
|The radio facility at ____ (''place'') is in operation (''or'' will be in operation in ____ hours).<br/>
''or''<br/>
Please have the ____ radio facility at ____ (''place'') put in operation.
|-
|'''QFT '''
|Between what heights above ____ (''datum'') has ice formation been observed [at ____ (''position or zone'')]? 
|Ice formation has been observed at ____ (''position or zone'') in the type of ____ and with an accretion rate of ____ between ____ (''figures and units'') and ____ (''figures and units'') heights above ____ (''datum'').
|-
|'''QFU '''
|What is the '''''magnetic''''' direction (''or'' runway number) of the runway to be used? 
|The '''''magnetic''''' direction (''or'' runway number) of the runway to be used is ____.{{efn|In response to '''QFU''' the '''''runway number''''' is always indicated by a two-figure group and the '''''magnetic direction''''' by a three-figure group.}}
|-
|'''QFV '''
|Are the floodlights switched on? 
|The floodlights are switched on.<br/>
''or''<br/> Please switch on the floodlights.
|-
|'''QFW '''
|What is the length of the runway in use in ____ (''units'')? 
|The length of runway ____ now in use is ____ (''figures and units'').
|-
|'''QFX '''
| 
|I am working (''or'' am going to work) on a fixed aerial.<br/>
''or''<br/> Work on a fixed aerial.
|-
|'''QFY '''
|Please report the present meteorological landing conditions [at ____ (''place'')].
|The present meteorological landing conditions at ____ (''place'') are ____.{{efn|When responding to '''QFY''' using other Q-codes, the information is sent in the following order: QAN, QBA, QNY, QBB, QNH and / or QFE and, if necessary, QMU, QNT, QBJ.}}
|-
|'''QFZ '''
|What is the aerodrome meteorological forecast for ____ (''place'') for the period ____ hours until ____ hours? 
|The aerodrome meteorological forecast for ____ (''place'') for the period ____ hours until ____ hours is ____.{{efn|When responding to '''QFZ''' using Q-codes the following sequence of answer (or advice) forms is to be used: QAN, QBA, QNY, QBB and, if necessary, QMU, QNT and QBJ.}}
|-
|'''QGC '''
| 
|There are obstructions to the ____ of ____ runway ____.
|-
|'''QGD '''
|Are there on my track any obstructions whose elevation equals or exceeds my altitude? 
|There are obstructions on your track ____ (''figures and units'') height above ____ (''datum'').
|-
|'''QGE '''
|What is my distance to your station (''or'' to ____)? 
|Your distance to my station (''or'' to ____) is ____ (''distance figures and units'').
|-
|'''QGH '''
|May I land using ____ (''procedure or facility'')? 
|You may land using ____ (''procedure or facility'').
|-
|'''QGK '''
|What track should I make good? <br/>
''or''<br/> What track are you making good? 
|Make good a track from ____ (''place'') on ____ degrees ____ ('''''true''' or '''magnetic'''''). <br/>
''or''<br/> I am making good a track from ____ (''place'') on ____ degrees ____ ('''''true''' or '''magnetic'''''). 
|-
|'''QGL '''
|May I enter the ____ (''control area or zone'') at ____ (''place'')? 
|You may enter the ____ (''control area or zone'') at ____ (''place'').
|-
|'''QGM '''
| 
|Leave the ____ (''control area or zone'').
|-
|'''QGN '''
|May I be cleared to land [at ____ (''place'')]? 
|You are cleared to land [at ____ (''place'')].
|-
|'''QGO '''
| 
|Landing is prohibited at ____ (''place'').
|-
|'''QGP '''
|What is my number for landing? 
|You are number ____ to land.
|-
|'''QGQ '''
|May I hold at ____ (''place'')? 
|Hold at ____ (''place'') at flight level/altitude ____ (''datum'') and await further clearance. 
|-
|'''QGT '''
| 
|Fly for ____ minutes on a heading what will enable you to maintain a track reciprocal to your present one. 
|-
|'''QGU '''
| 
|Fly for ____ minutes on a '''''magnetic''''' heading of ____ degrees.
|-
|'''QGV '''
|Do you see me?<br/>
''or''<br/>
Can you see the aerodrome? <br/>
''or''<br/> Can you see ____ (''aircraft'')? 
|I see you at ____ (''cardinal or quadrantal point of direction''). <br/>
''or''<br/> I can see the aerodrome.<br/>
''or''<br/> I can see ____ (aircraft).
|-
|'''QGW '''
|Does my landing gear appear to be down and in place? 
|Your landing gear appears to be down and in place.
|-
|'''QGZ '''
| 
|Hold on ____ direction of ____ facility.
|-
|'''QHE '''
|Will you inform me when you are on ____ leg of approach? 
|I am on ____ of approach.<br/> 1. cross-wind leg<br/> 2. down-wind leg<br/> 3. base leg<br/> 4. final leg
|-
|'''QHG '''
|May I enter traffic circuit at flight level/altitude ____?
|Cleared to enter traffic circuit at flight level/altitude ____.
|-
|'''QHH '''
|Are you making an emergency landing? 
|I am making an emergency landing. <br/>
''or''<br/> Emergency landing being made at ____ (''place''). All aircraft below flight level/altitude ____ and within a distance of ____ (''figures and units'') leave ____ (''place or headings'').
|-
|'''QHI '''
|Are you [''or'' is ____(''place'')] ____.<br/> 1. waterborne?<br/> 2. on land? 
|I am [''or'' ____ (''place'') is] ____ at ____ hours.<br/> 1. waterborne<br/> 2. on land<br/> 
|-
|'''QHQ '''
|May I make a ____ approach [at ____ (''place'')]? <br/>
''or''<br/> Are you making a ____ approach? 
|You may make a ____ approach [at ____ (''place'')]. <br/>
''or''<br/> I am making a ____ approach. 
|-
|'''QHZ '''
|Shall I circle the aerodrome (''or'' go around)? 
|Circle the aerodrome (''or'' go around).
|-
|'''QIC '''
|May I establish communication with ____ radio station on ____ kHz (''or'' MHz) [now ''or'' at ____ hours]? 
|Establish communication with ____ radio station on ____ kHz. (''or'' MHz) [now ''or'' at ____ hours].<br/>
''or''<br/>
I will establish communication with ____ radio station on ____ kHz (''or'' MHz) [now ''or'' at ____ hours].
|-
|'''QIF '''
|What frequency is ____ using? 
|____ is using ____ kHz (''or'' MHz). 
|-
|'''QJA '''
|Is my ____ reversed?<br/> 1. tape<br/> 2. mark and space<br/> 
|Your ____ is reversed.<br/> 1. tape<br/> 2. mark and space<br/>
|-
|'''QJB '''
|Will you use ____.<br/> 1. radio?<br/> 2. cable?<br/> 3. telegraph?<br/> 4. teletypewriter?<br/> 5. telephone?<br/> 6. receiver?<br/> 7. transmitter?<br/> 8. reperforator?         
|I will use ____.<br/> 1. radio.<br/> 2. cable.<br/> 3. telegraph.<br/> 4. teletypewriter.<br/> 5. telephone.<br/> 6. receiver.<br/> 7. transmitter.<br/> 8. reperforator.
|-
|'''QJC '''
|Will you check your ____.<br/> 1. transmitter distributor?<br/> 2. auto-head?<br/> 3. perforator?<br/> 4. reperforator?<br/> 5. printer?<br/> 6. printer motor?<br/> 7. keyboard?<br/> 8. antenna system?  
|I will check my ____.<br/> 1. transmitter distributor.<br/> 2. auto-head.<br/> 3. perforator.<br/> 4. reperforator.<br/> 5. printer.<br/> 6. printer motor.<br/> 7. keyboard.<br/> 8. antenna system.
|-
|'''QJD '''
|Am I transmitting ____.<br/> 1. in letters?<br/> 2. in figures? 
|You are transmitting ____.<br/> 1. in letters<br/> 2. in figures. 
|-
|'''QJE '''
|Is my frequency shift ____.<br/> 1. too wide?<br/> 2. too narrow?<br/> 3. correct? 
|Your frequency shift is ____.<br/> 1. too wide.<br/> 2. too narrow (by ____ cycles).<br/> 3. correct. 
|-
|'''QJF '''
| 
|My signal as checked by monitor ____ is satisfactory ____.<br/> 1. locally.<br/> 2. as radiated. 
|-
|'''QJG '''
|Shall I revert to automatic relay? 
|Revert to automatic relay.
|-
|'''QJH '''
|Shall I run ____<br/> 1. my test tape?<br/> 2. a test sentence? 
|Run ____<br/> 1. your test tape.<br/> 2. a test sentence. 
|-
|'''QJI '''
|Will you transmit a continuous ____.<br/> 1. mark?<br/> 2. space? 
|I am transmitting a continuous ____.<br/> 1. mark.<br/> 2. space. 
|-
|'''QJK '''
|Are you receiving ____.<br/> 1. a continuous mark?<br/> 2. a continuous space?<br/> 3. a mark bias?<br/> 4. a space bias? 
|I am receiving ____.<br/> 1. a continuous mark.<br/> 2. a continuous space.<br/> 3. a mark bias.<br/> 4. a space bias. 
|-
|'''QKC '''
| 
|The sea conditions (at ____ position) ____.<br/> 1. permit alighting but not take-off.<br/> 2. render alighting extremely hazardous. 
|-
|'''QKF '''
|May I be relieved (at ____ hours)?
|You may expect to be relieved at ____ hours [by ____].<br/> 1. aircraft ____ (''identification'') (type ____) <br/> 2. [vessel whose call sign is ____ (''call sign'')] ''and / or'' [whose name is ____ (''name'')]. 
|-
|'''QKG '''
|Will relief take place when ____ (''identification'') establishes ____.<br/> 1. visual,<br/> 2. communications,<br/> contact with survivors?
|Relief will take place when ____ (''identification'') establishes ____.<br/> 1. visual,<br/> 2. communications,<br/> contact with survivors.
|-
|'''QKH '''
|Report details of the parallel sweep (track) search being (''or'' to be) conducted?<br/>
''or''<br/>
In the parallel sweep (track) search being (''or'' to be) conducted, what is (are) ____.<br/>
1. the direction of sweeps,<br/>
2. the separation between sweeps,<br/>
3. the flight level/altitude ____ employed in the search pattern?
|The parallel sweep (track) search is being (''or'' to be) conducted ____.<br/>
1. with direction of sweeps ____ degrees ____ ('''''true''' or '''magnetic''''').<br/>
2. with ____ (''distance figures and units'') separation between sweeps.<br/>
3. at flight level/altitude ____.
|-
|'''QKN '''
| 
|Aircraft plotted (believed to be you) in position ____ on track ____ degrees at ____ hours. 
|-
|'''QKO '''
|What other units are (''or'' will be) taking part in the operation [____ (''identification of operation'')]?
|In the operation [____ (''identification'')], the following units are (''or'' will be) taking part ____ (''name of units'').<br/>
''or''<br/>
____ (''name'') unit is taking part in operation [____ (''identification''] (with effect from ____ hours).
|-
|'''QKP '''
|Which pattern of search is being followed?
|The search pattern is ____.<br/> 1. parallel sweep.<br/> 2. square search.<br/> 3. creeping line ahead.<br/> 4. track crawl.<br/> 5. contour search.<br/> 6. combined search by aircraft and ship.<br/> 7. ____ (''specify'').
|-
|'''QLB '''
|Will you monitor ____ station and report regarding range, quality, etc.? 
|I have monitored ____ station and report (''briefly'') as follows ____.
|-
|'''QLH '''
|Will you use simultaneous keying on ____ frequency and ____ frequency? 
|I will now key simultaneously on ____ frequency and ____ frequency. 
|-
|'''QLV '''
|Is the ____ radio facility still required? 
|The ____ radio facility is still required. 
|-
|'''QMH '''
| 
|Shift to transmit and receive on ____ kHz (''or'' ____ MHz.); if communication is not established within 5 minutes, revert to present frequency. 
|-
|'''QMI '''
|Report the vertical distribution of cloud [at ____ (''position or zone'')] as observed from your aircraft. 
|The vertical distribution of cloud as observed from my aircraft at ____ hours at ____.(''position or zone'') is :<br/>
lowest layer observed* ____ eights (____ type) with base of ____ (''figures and units'') and tops of ____ (''figures and units'')<br/>
[''*and similarly in sequence for each of the layers observed.'']<br/>
height above ____ (''datum'').
|-
|'''QMU '''
|What is the surface temperature at ____ (''place'') and what is the dew point temperature at that place? 
|The surface temperature at ____ (''place'') at ____ hours is ____ degrees and the dew point temperature at that time and place is ____ degrees. 
|-
|'''QMW '''
|At ____ (''position or zone'') what is (are) the flight level(s)/altitude(s) ____ of the zero Celsius isotherm(s)? 
|At ____ (''position or zone'') the zero Celsius isotherm(s) is (are) at flight level(s)/altitude(s) ____.
|-
|'''QMX '''
|What is the air temperature [at ____ (''position or zone'')] (at ____ hours) at flight level/altitude ____? 
|At ____ (''position or zone'') at ____ hours the air temperature is ____ (''degrees and units'') at flight level/altitude ____.{{efn|Aircraft reporting '''QMX''' information will transmit the temperature figures as ''corrected for airspeed''.}}
|-
|'''QMZ '''
|Have you any amendments to the flight forecast in respect of section of route yet to be traversed? 
|The following amendment(s) should be made to the flight forecast ____.{{efn|If no amendments, respond to '''QMZ?''' with signal '''QMZ NIL'''.}} 
|-
|'''QNE '''
|What indication will my altimeter give on landing at ____ (''place'') at ____ hours, my sub-scale being set to 1013.2 millibars (29.92 inches)? 
|On landing at ____ (''place'') at ____ hours, with your sub-scale being set to 1013.2 millibars (29.92 inches), your altimeter will indicate ____ (''figures and units''). 
|-
|'''QNH '''
|What should I set on the subscale of my altimeter so that the instrument would indicate its elevation if my aircraft were on the ground at your station? 
|If you set the subscale of your altimeter to read ____ millibars, the instrument would indicate its elevation if your aircraft were on the ground at my station at ____ hours.{{efn|When the setting in response to '''QNH?''' is given in hundredths of an inch (instead of millibars), the abbreviation "INS" is used to identify the units.}}
|-
|'''QNI '''
|Between what heights above ____ (''datum'') has turbulence been observed at ____ (''position or zone'')? 
|Turbulence has been observed at ____ (''position or zone'') with an intensity of ____ between ____ (''figures and units'') and ____ (''figures and units'') heights above ____ (''datum''). 
|-
|'''QNO '''
| 
|I am not equipped to give the information (''or'' provide the facility) requested. 
|-
|'''QNR '''
| 
|I am approaching my point of no return.
|-
|'''QNT '''
|What is the maximum speed of the surface wind at ____ (''place'')? 
|The maximum speed of the surface wind at ____ (''place'') at ____ hours is ____ (''speed figures and units''). 
|-
|'''QNY '''
|What is the present weather and the intensity thereof at ____ (''place, position or zone'')? 
|The present weather and intensity thereof at ____ (''place, position or zone'') at ____ hours is ____.{{efn|Regarding response to '''QNY?''':<br/>
* When present weather information is transmitted by a ground station, the abbreviations shall be selected from those specified in Annex&nbsp;3, paragraph&nbsp;4.8.2.
* When present weather information is transmitted by an aircraft, the information shall be selected from items&nbsp;10–12 of the [[AIREP]] form.}} 
|}

===Maritime Mobile Service (QOA–QQZ)===
{{Main|Maritime Mobile Service Q Codes}}

This assignment is specified in ''RECOMMENDATION ITU-R M.1172''.<ref>{{cite web |title=RECOMMENDATION 1172 |id=ITU-R M.1172 |url=http://life.itu.int/radioclub/rr/m1172.htm |url-status=dead |archive-url=https://web.archive.org/web/20150421175748/http://life.itu.int/radioclub/rr/m1172.htm |archive-date=2015-04-21}}</ref>

Q signals are not substantially used in the maritime service. Morse code is now very rarely used for maritime communications, but in isolated maritime regions like Antarctica and the South Pacific the use of Q-codes continues. Q-codes still work when HF voice circuits are not possible due to atmospherics and the nearest vessel is one ionospheric hop away.

{| class="wikitable"
|-
! 
!'''Question ?'''
!'''Answer or advice'''
|-
|'''QOA '''
|Can you communicate by radiotelegraphy (500&nbsp;kHz)? 
|I can communicate by radiotelegraphy (500&nbsp;kHz). 
|-
|'''QOB '''
|Can you communicate by radiotelephony (2.182&nbsp;MHz)? 
|I can communicate by radiotelephony (2.182&nbsp;MHz). 
|-
|'''QOC '''
|Can you communicate by radiotelephony (channel 16 – frequency 156.8&nbsp;MHz)? 
|I can communicate by radiotelephony (channel 16 – frequency 156.8&nbsp;MHz). 
|-
|'''QOD '''
|Can you communicate with me in ____?<br/>
:{|
  |-
  | 0. Dutch   || 5. Italian
  |-
  | 1. English || 6. Japanese
  |-
  | 2. French  || 7. Norwegian
  |-
  | 3. German &nbsp; || 8. Russian
  |-
  | 4. Greek   || 9. Spanish
  |} 
|I can communicate with you in ____.<br/>
:{|
  |-
  | 0. Dutch   || 5. Italian
  |-
  | 1. English || 6. Japanese
  |-
  | 2. French  || 7. Norwegian
  |-
  | 3. German &nbsp; || 8. Russian
  |-
  | 4. Greek   || 9. Spanish
  |} 
|-
|'''QOE '''
|Have you received the safety signal sent by ____ (''name and/or call sign'')? 
|I have received the safety signal sent by ____ (''name and/or call sign''). 
|-
|'''QOF '''
|What is the commercial quality of my signals? 
|The quality of your signals is ____.<br/> 1. not commercial<br/> 2. marginally commercial<br/> 3. commercial. 
|-
|'''QOG '''
|How many tapes have you to send? 
|I have ____ tapes to send. 
|-
|'''QOH '''
|Shall I send a phasing signal for ____ seconds? 
|Send a phasing signal for ____ seconds. 
|-
|'''QOI '''
|Shall I send my tape? 
|Send your tape. 
|-
|'''QOJ '''
|Will you listen on ____ kHz (''or'' MHz) for signals of emergency position-indicating radiobeacons? 
|I am listening on ____ kHz (''or'' MHz) for signals of emergency position-indicating radiobeacons. 
|-
|'''QOK '''
|Have you received the signals of an emergency position-indicating radiobeacon on ____ kHz (''or'' MHz)? 
|I have received the signals of an emergency position-indicating radiobeacon on ____ kHz (''or'' MHz). 
|-
|'''QOL '''
|Is your vessel fitted for reception of selective calls? If so, what is your selective call number or signal? 
|My vessel is fitted for the reception of selective calls. My selective call number or signal is ____.
|-
|'''QOM '''
|On what frequencies can your vessel be reached by a selective call? 
|My vessel can be reached by a selective call on the following frequency/ies ____ (periods of time to be added if necessary). 
|-
|'''QOO '''
|Can you send on any working frequency? 
|I can send on any working frequency. 
|-
|'''QOT '''
|Do you hear my call; what is the approximate delay in minutes before we may exchange traffic? 
|I hear your call; the approximate delay is ____ minutes. 
|}

===All services (QRA–QUZ)===
First defined by the Washington 1927 ITU Radio Regulations. Later defined by ITU-R in Appendix 9 to the Radio Regulations Annex to the ''International Telecommunications Convention'' (Atlantic City, 1947). The current callsign table is found in ITU-R Appendix 42. Current interpretation of the Q-code can be found in ITU-R Appendices 14 and 15.

ITU Radio Regulations 1990, Appendix 13: Miscellaneous Abbreviations and Signals to be Used in Radiotelegraphy Communications Except in the Maritime Mobile Service:<ref name="AP-1994-ch13"></ref>
                                                                                                                                                                                                                
{| class="wikitable"
|-
! 
!'''Question ?'''
!'''Answer or advice'''
|-
|'''QRA '''
|What is the name of your vessel (''or'' station)? 
|The name of my vessel (''or'' station) is ____.
|-
|'''QRB '''
|How far approximately are you from my station? 
|The approximate distance between our stations is ____ nautical miles (''or'' km). 
|-
|'''QRC '''
|By what private enterprise (''or'' state administration) are the accounts for charges for your station settled? 
|The accounts for charges of my station are settled by the private enterprise ____ (''or'' state administration). 
|-
|'''QRD '''
|Where are you bound for and where are you from? 
|I am bound for ____ from ____.
|-
|'''QRE '''
|What is your estimated time of arrival at ____ (''or'' over ____) (''place'')? 
|My estimated time of arrival at ____ (''or'' over ____) (''place'') is ____ hours. 
|-
|'''QRF '''
|Are you returning to ____ (''place'')? 
|I am returning to ____ (''place''). <br/>
''or''<br/> Return to ____ (''place''). 
|-
|'''QRG '''
|Will you tell me my exact frequency (''or'' that of ____)? 
|Your exact frequency (''or'' that of ____) is ____ kHz (''or'' MHz). 
|-
|'''QRH '''
|Does my frequency vary? 
|Your frequency varies. 
|-
|'''QRI '''
|How is the tone of my transmission? 
|The tone of your transmission is ____.<br/>
:{|
  |-
  | 1. good
  |-
  | 2. variable
  |-
  | 3. bad
  |}
|-
|'''QRJ '''
|How many radiotelephone calls have you to book? 
|I have ____ radiotelephone calls to book. 
|-
|'''QRK '''
|What is the intelligibility of my signals (''or'' those of ____)? 
|The intelligibility of your signals (''or'' those of ____) is ____<br/>
:{|
  |-
  | 1. bad
  |-
  | 2. poor
  |-
  | 3. fair
  |-
  | 4. good
  |-
  | 5. excellent
  |}
|-
|'''QRL '''
|Are you busy? 
|I am busy (''or'' I am busy with ____). Please do not interfere. 
|-
|'''QRM '''
|Are you being interfered with?<ref name="AP-1994-ch13"/> <br/>
''or''<br/> Is my transmission being interfered with?<ref name="AP-1994-ch14"/> 
|I am being interfered with<ref name="AP-1994-ch13"/> <br/>
''or''<br/> Your transmission is being interfered with ____.<ref name="AP-1994-ch14"/><br/>
:{|
  |-
  | 1. nil
  |-
  | 2. slightly
  |-
  | 3. moderately
  |-
  | 4. severely
  |-
  | 5. extremely
  |}
|-
|'''QRN '''
|Are you troubled by static? 
|I am troubled by static (____).<br/>
:{|
  |-
  | 1. nil
  |-
  | 2. slightly
  |-
  | 3. moderately
  |-
  | 4. severely
  |-
  | 5. extremely
  |}
|-
|'''QRO '''
|Shall I increase transmitter power? 
|Increase transmitter power. 
|-
|'''QRP '''
|Shall I decrease transmitter power? 
|Decrease transmitter power. 
|-
|'''QRQ '''
|Shall I send faster? 
|Send faster (____ words per minute). 
|-
|'''QRR '''
|Are you ready for automatic operation? 
|I am ready for automatic operation. Send at ____ words per minute. 
|-
|'''QRS '''
|Shall I send more slowly? 
|Send more slowly (____ words per minute). 
|-
|'''QRT '''
|Shall I stop sending? 
|Stop sending. 
|-
|'''QRU '''
|Have you anything for me? 
|I have nothing for you. 
|-
|'''QRV '''
|Are you ready? 
|I am ready. 
|-
|'''QRW '''
|Shall I inform ____ that you are calling him on ____ kHz (''or'' MHz)? 
|Please inform ____ that I am calling him on ____ kHz (''or'' MHz). 
|-
|'''QRX '''
|When will you call me again? 
|I will call you again at ____ hours (on ____ kHz (''or'' MHz)). 
|-
|'''QRY '''
|What is my turn?<br/> (''relates to shared communication networks''). 
|Your turn is number ____ (''or according to any other indication'').<br/> (''relates to shared communication networks''). 
|-
|'''QRZ '''
|Who is calling me? 
|You are being called by ____ (on ____ kHz (''or'' MHz)). 
|-
|'''QSA '''
|What is the strength of my signals (''or'' those of ____)? 
|The strength of your signals (''or'' those of ____) is ____.<br/>
:{|
  |-
  | 1. scarcely perceptible
  |-
  | 2. weak
  |-
  | 3. fairly good
  |-
  | 4. good
  |-
  | 5. very good
  |}  
|-
|'''QSB '''
|Are my signals fading? 
|Your signals are fading. 
|-
|'''QSC '''
|Are you a cargo vessel?<ref name="AP-1994-ch13/> <br/>
''or''<br/> Are you a low traffic ship?<ref name="AP-1994-ch14"/> 
|I am a cargo vessel.<ref name="AP-1994-ch13"/> <br/>
''or''<br/> I am a low traffic ship.<ref name="AP-1994-ch14"/> 
|-
|'''QSD '''
|Is my keying defective?<ref name="AP-1994-ch13"/> <br/>
''or''<br/> Are my signals mutilated?<ref name="AP-1994-ch14"/> 
|Your keying is defective.<ref name="AP-1994-ch13"/> <br/>
''or''<br/> Your signals are mutilated.<ref name="AP-1994-ch14"/>
|-
|'''QSE*'''
|What is the estimated drift of the survival craft? 
|The estimated drift of the survival craft is ____ (''figures and units''). 
|-
|'''QSF*'''
|Have you effected rescue? 
|I have effected rescue and am proceeding to ____ base (with ____ persons injured requiring ambulance). 
|-
|'''QSG '''
|Shall I send ____ telegrams at a time? 
|Send ____ telegrams at a time. 
|-
|'''QSH '''
|Are you able to home on your direction-finding equipment? 
|I am able to home on my D/F equipment (on station ____). 
|-
|'''QSI '''
| 
|I have been unable to break in on your transmission. <br/>
''or''<br/> Will you inform ____ (''call sign'') that I have been unable to break in on his transmission (on ____ kHz (''or'' MHz)).       
|-
|'''QSJ '''
|What is the charge to be collected to ____ including your internal charge? 
|The charge to be collected to ____ including my internal charge is ____ francs. 
|-
|'''[[QSK operation (full break-in)|QSK]] '''
|Can you hear me between your signals and if so can I break in on your transmission? 
|I can hear you between my signals; break in on my transmission. 
|-
|'''[[QSL card|QSL]] '''
|Can you acknowledge receipt? 
|I am acknowledging receipt. 
|-
|'''QSM '''
|Shall I repeat the last telegram which I sent you (''or'' some previous telegram)? 
|Repeat the last telegram which you sent me (''or'' telegram(s) number(s) ____). 
|-
|'''QSN '''
|Did you hear me (''or'' ____ (''call sign'')) on ____ kHz (''or'' MHz)? 
|I did hear you (''or'' ____ (''call sign'')) on ____ kHz (''or'' MHz). 
|-
|'''QSO '''
|Can you communicate with ____ direct (''or'' by relay)? 
|I can communicate with ____ direct (''or'' by relay through ____). 
|-
|'''QSP '''
|Will you relay to ____ free of charge? 
|I will relay to ____ free of charge. 
|-
|'''QSQ '''
|Have you a doctor on board (''or'' is ____ (''name of person'') on board)? 
|I have a doctor on board (''or'' ____ (''name of person'') is on board). 
|-
|'''QSR '''
|Shall I repeat the call on the calling frequency? 
|Repeat your call on the calling frequency; did not hear you (''or'' have interference). 
|-
|'''QSS '''
|What working frequency will you use? 
|I will use the working frequency ____ kHz (''or'' MHz) (''in the HF bands normally only the last three figures of the frequency need be given''). 
|-
|'''QSU '''
|Shall I send or reply on this frequency (''or'' on ____ kHz (''or'' MHz)) (with emissions of class ____)? 
|Send or reply on this frequency (''or'' on ____ kHz (''or'' MHz)) (with emissions of class ____). 
|-
|'''QSV '''
|Shall I send a series of Vs on this frequency (''or'' on ____ kHz (''or'' MHz))? 
|Send a series of Vs on this frequency (''or'' on ____ kHz (''or'' MHz)). 
|-
|'''QSW '''
|Will you send on this frequency (''or'' on ____ kHz (''or'' MHz)) (with emissions of class ____)? 
|I am going to send on this frequency (''or'' on ____ kHz (''or'' MHz)) (with emissions of class ____). 
|-
|'''QSX '''
|Will you listen to ____ (''call sign(s)'') on ____ kHz (''or'' MHz)?<ref name="AP-1994-ch13"/> <br/>
''or''<br/> Will you listen to ____ (''call sign(s)'') on ____ kHz (''or'' MHz), or in the bands ____ / channels ____ ?<ref name="AP-1994-ch14"/> 
|I am listening to ____ (''call sign(s)'') on ____ kHz (''or'' MHz).<ref name="AP-1994-ch13"/> <br/>
''or''<br/> I am listening to ____ (''call sign(s)'') on ____ kHz (''or'' MHz), or in the bands ____ / channels ____.<ref name="AP-1994-ch14"/> 
|-
|'''QSY '''
|Should I change to transmission on another frequency? If so what one?
|Change to transmission on another frequency [''or'' on ____ kHz (''or'' MHz)]. 
|-
|'''QSZ '''
|Shall I send each word or group more than once? 
|Send each word or group twice (''or'' ____ times). 
|-
|'''QTA '''
|Shall I cancel telegram (''or'' message) number ____ ?
|Cancel telegram (''or'' message) number ____.
|-
|'''QTB '''
|Do you agree with my counting of words? 
|I do not agree with your counting of words; I will repeat the first letter or digit of each word or group. 
|-
|'''QTC '''
|How many telegrams have you to send? 
|I have ____ telegrams for you (''or'' for ____). 
|-
|'''QTD*'''
|What has the rescue vessel or rescue aircraft recovered? 
|____ (''identification'') has recovered ____.<br/>
:{|
  |-
  | 1. ____ (''number'') survivors
  |-
  | 2. wreckage
  |-
  | 3. ____ (''number'') bodies
  |} 
|-
|'''QTE '''
|What is my TRUE bearing from you? <br/>
''or''<br/> What is my TRUE bearing from ____ (''call sign'')? <br/>
''or''<br/> What is the TRUE bearing of ____ (''call sign'') from ____ (''call sign'')?      
|Your TRUE bearing from me is ____ degrees at ____ hours. <br/>
''or''<br/> Your TRUE bearing from ____ (''call sign'') was ____ degrees at ____ hours. <br/>
''or''<br/> The TRUE bearing of ____ (''call sign'') from ____ (''call sign'') was ____ degrees        at ____ hours.        
|-
|'''QTF '''
|Will you give me the position of my station according to the bearings taken by the direction-finding stations which you control? 
|The position of your station according to the bearings taken by the D/F stations which I control was ____ latitude, ____ longitude (''or other indication of position''), class ____ at ____ hours.  
|-
|'''QTG '''
|Will you send two dashes of ten seconds each followed by your call sign (repeated ____ times) (on ____ kHz (''or'' MHz))? <br/>
''or''<br/> Will you request ____ to send two dashes of ten seconds followed by his call sign (repeated ____        times) on ____ kHz (''or'' MHz)?         
|I am going to send two dashes of ten seconds each followed by my call sign (repeated ____ times) (on ____ kHz (''or'' MHz)). <br/>
''or''<br/> I have requested ____ to send two dashes of ten seconds followed  by his call sign (repeated ____        times) on ____ kHz (''or'' MHz).        
|-
|'''QTH '''
|What is your position in latitude and longitude (''or according to any other indication'')? 
|My position is ____ latitude, ____ longitude (''or according to any other indication''). 
|-
|'''QTI '''
|What is your TRUE track?<ref name="AP-1994-ch13"/>
|My TRUE track is ____ degrees.<ref name="AP-1994-ch13"/> 
|-
|'''QTI*'''
|What is your TRUE course?<ref name="AP-1994-ch14"/> 
|My TRUE course is ____ degrees.<ref name="AP-1994-ch14"/> 
|-
|'''QTJ*'''
|What is your speed? <br/>
(''Requests the speed of a ship or aircraft through the water or air respectively''). 
|My speed is ____ knots (''or'' ____ kilometres per hour or ____ statute miles per hour). <br/>
(''Indicates the speed of a ship or aircraft through the water or air respectively''). 
|-
|'''QTK*'''
|What is the speed of your aircraft in relation to the surface of the Earth? 
|The speed of my aircraft in relation to the surface of the Earth is ____ knots (''or'' ____ kilometres per hour or ____ statute miles per hour). 
|-
|'''QTL*'''
|What is your TRUE heading? 
|My TRUE heading is ____ degrees. 
|-
|'''QTM*'''
|What is your MAGNETIC heading? 
|My MAGNETIC heading is ____ degrees. 
|-
|'''QTN '''
|At what time did you depart from ____ (''place'')? 
|I departed from ____ (''place'') at ____ hours. 
|-
|'''QTO '''
|Have you left dock (''or'' port)? <br/>
''or''<br/> Are you airborne? 
|I have left dock (''or'' port). <br/>
''or''<br/> I am airborne. 
|-
|'''QTP '''
|Are you going to enter dock (''or'' port)? <br/>
''or''<br/> Are you going to alight (''or'' land)? 
|I am going to enter dock (''or'' port). <br/>
''or''<br/> I am going to alight (''or'' land). 
|-
|'''QTQ '''
|Can you communicate with my station by means of the [[International Code of Signals]] (INTERCO)? 
|I am going to communicate with your station by means of the International Code of Signals (INTERCO). 
|-
|'''QTR '''
|What is the correct time? 
|The correct time is ____ hours. 
|-
|'''QTS '''
|Will you send your call sign for tuning purposes or so that your frequency can be measured now (''or'' at ____ hours) on ____ kHz (''or'' MHz)?<ref name="AP-1994-ch13"/> <br/>
''or''<br/> Will you send your call sign (''and/or'' name) for ____ seconds?<ref name="AP-1994-ch14"/> 
|I will send my call sign for tuning purposes or so that my frequency may be measured now (''or'' at ____ hours) on ____ kHz (''or'' MHz).<ref name="AP-1994-ch13"/> <br/>
''or''<br/> I will send my call sign (''and/or'' name) for ____ seconds.<ref name="AP-1994-ch14"/> 
|-
|'''QTT '''
| 
|The identification signal which follows is superimposed on another transmission. 
|-
|'''QTU '''
|What are the hours during which your station is open? 
|My station is open from ____ to ____ hours. 
|-
|'''QTV '''
|Shall I stand guard for you on the frequency of ____ kHz (''or'' MHz) (from ____ to ____ hours)? 
|Stand guard for me on the frequency of ____ kHz (''or'' MHz) (from ____ to ____ hours). 
|-
|'''QTW*'''
|What is the condition of survivors? 
|Survivors are in ____ condition and urgently need ____.
|-
|'''QTX '''
|Will you keep your station open for further communication with me until further notice (''or'' until ____ hours)? 
|I will keep my station open for further communication with you until further notice (''or'' until ____ hours). 
|-
|'''QTY*'''
|Are you proceeding to the position of incident and if so when do you expect to arrive? 
|I am proceeding to the position of incident and expect to arrive at ____ hours (on ____ (''date'')). 
|-
|'''QTZ*'''
|Are you continuing the search? 
|I am continuing the search for ____ (aircraft, ship, survival craft, survivors or wreckage). 
|-
|'''QUA '''
|Have you news of ____ (''call sign'')? 
|Here is news of ____ (''call sign''). 
|-
|'''QUB*'''
|Can you give me in the following order information concerning: the direction in degrees TRUE and speed of the surface wind; visibility; present weather; and amount, type and height of base of cloud above surface elevation at ____ (''place of observation'')? 
|Here is the information requested: ____ (''The units used for speed and distances should be indicated.'') 
|-
|'''QUC '''
|What is the number (''or other indication'') of the last message you received from me (''or'' from ____ (''call sign''))? 
|The number (''or other indication'') of the last message I received from you (''or'' from ____ (''call sign'')) is ____.
|-
|'''QUD '''
|Have you received the urgency signal sent by ____ (''call sign of mobile station'')? 
|I have received the urgency signal sent by ____ (''call sign of mobile station'') at ____ hours. 
|-
|'''QUE '''
|Can you use telephony in ____ (''language''), with interpreter if necessary; if so, on what frequencies?<ref name="AP-1994-ch13"/> <br/>
''or''<br/> Can you speak in ____ (''language''), – with interpreter if necessary; if so, on what frequencies?<ref name="AP-1994-ch14"/> 
|I can use telephony in ____ (''language'') on ____ kHz (''or'' MHz).<ref name="AP-1994-ch13"/> <br/>
''or''<br/> I can speak in ____ (''language'') on ____ kHz (''or'' MHz).<ref name="AP-1994-ch14"/> 
|-
|'''QUF '''
|Have you received the distress signal sent by ____ (''call sign of mobile station'')? 
|I have received the distress signal sent by ____ (''call sign of mobile station'') at ____ hours. 
|-
|'''QUG '''
|Will you be forced to alight (''or'' land)?<ref name="AP-1994-ch13"/> 
|I am forced to alight (''or'' land) immediately. <br/>
''or''<br/> I shall be forced to alight (''or'' land) at ____ (position or place) at ____ hours.<ref name="AP-1994-ch13"/>
|-
|'''QUH*'''
|Will you give me the present barometric pressure at sea level? 
|The present barometric pressure at sea level is ____ (''units''). 
|-
|'''QUI '''
|Are your navigation lights working?<ref name="AP-1994-ch13"/>
|My navigation lights are working.<ref name="AP-1994-ch13"/>
|-
|'''QUJ '''
|Will you indicate the TRUE track to reach you (''or'' ____)?<ref name="AP-1994-ch13"/> 
|The TRUE track to reach me (''or'' ____) is ____ degrees at ____ hours.<ref name="AP-1994-ch13"/> 
|-
|'''QUK '''
|Can you tell me the condition of the sea observed at ____ (place or coordinates)?<ref name="AP-1994-ch13"/> 
|The sea at ____ (place or coordinates) is ____.<ref name="AP-1994-ch13"/> 
|-
|'''QUL '''
|Can you tell me the swell observed at ____ (place or coordinates)?<ref name="AP-1994-ch13"/> 
|The swell at ____ (place or coordinates) is ____.<ref name="AP-1994-ch13"/>
|-
|'''QUM '''
|May I resume normal working? 
|Normal working may be resumed. 
|-
|'''QUN '''
|''1. When directed to all stations:''<ref name="AP-1994-ch13"/><ref name="AP-1994-ch14"/><br/>
:Will vessels
:: (in my immediate vicinity ____)
''or''<br/>
:: (in the vicinity of ____ latitude, ____ longitude)
''or''<br/>
:: (in the vicinity of ____)
: please indicate their position, TRUE course, and speed?
''or''<br/>
''2. When directed to a single station:''<ref name="AP-1994-ch1"/><br/>
: Please indicate your position, TRUE course, and speed. 
| My position, TRUE course and speed are ____.
|-
|'''QUO*'''
| Shall I search for ____ <br/>
:{|
  |-
  | 1. aircraft
  |-
  | 2. ship
  |-
  | 3. survival craft
  |}
in the vicinity of ____ latitude, ____ longitude (''or according to any other indication'')? 
| Please search for ____ <br/>
:{|
  |-
  | 1. aircraft
  |-
  | 2. ship
  |-
  | 3. survival craft
  |}
in the vicinity of ____ latitude, ____ longitude (''or according to any other indication''). 
|-
|'''QUP '''
|Will you indicate your position by<br/>
:{|
  |-
  | 1. searchlight
  |-
  | 2. black smoke trail
  |-
  | 3. pyrotechnic lights?
  |}
|My position is indicated by<br/>
:{|
  |-
  | 1. searchlight
  |-
  | 2. black smoke trail
  |-
  | 3. pyrotechnic lights
  |}
|-
|'''QUQ '''
|Shall I train my searchlight nearly vertical on a cloud, occulting if possible and, if your aircraft is seen, deflect the beam up wind and on the water (''or'' land) to facilitate your landing? 
|Please train your searchlight on a cloud, occulting if possible and, if my aircraft is seen or heard, deflect the beam up wind and on the water (''or'' land) to facilitate my landing.<ref name="AP-1994-ch13"/> 
|-
|'''QUR*'''
| Have survivors ____.<br/>
:{|
  |-
  | 1. received survival equipment
  |-
  | 2. been picked up by rescue vessel
  |-
  | 3. been reached by ground rescue party?
  |}
| Survivors ____.
:{|
  |-
  | 1. are in possession of survival equipment<br/> &emsp; dropped by ____.
  |-
  | 2.  have been picked up by a rescue vessel
  |-
  | 3. have been reached by a<br/> &emsp; ground rescue party
  |}
|-
|'''QUS*'''
|Have you sighted survivors or wreckage? If so, in what position? 
|Have sighted ____.<br/>
:{|
  |-
  | 1. survivors in water
  |-
  | 2. survivors on rafts
  |-
  | 3. wreckage<br/> &emsp; at position ____ latitude, ____ longitude<br/> &emsp; (''or according to any other indication'')
  |}
|-
|'''QUT*'''
|Is position of incident marked? 
|Position of incident is marked by ____.<br/>
:{|
  |-
  | 1. flame or smoke float
  |-
  | 2. sea marker
  |-
  | 3. sea marker dye
  |-
  | 4. ____ (''specify other marking'')
  |} 
|-
|'''QUU*'''
|Shall I home ship or aircraft to my position? 
|Home ship or aircraft ____ (''call sign'') ____.<br/>
:{|
  |-
  | 1. to your position by transmitting your<br/> &emsp; call sign and long dashes<br/> &emsp; on ____ kHz (''or'' MHz)
  |-
  | 2. by transmitting on ____ kHz (''or'' MHz)<br/> &emsp; TRUE track to reach you.
  |} 
|-
|'''QUW*'''
|Are you in the search area designated as ____ (''designator or latitude and longitude'')? 
|I am in the ____ (''designation'') search area. 
|-
|'''QUX '''
|Do you have any navigational warnings or gale warnings in force?<ref name="AP-1994-ch14"/> 
|I have the following navigational warning(s) or gale warning(s) in force: ____.<ref name="AP-1994-ch14"/> 
|-
|'''QUY*'''
|Is position of survival craft marked? 
|Position of survival craft was marked at ____ hours by ____.<br/>
:{|
  |-
  | 1. flame or smoke float
  |-
  | 2. sea marker
  |-
  | 3. sea marker dye
  |-
  | 4. ____ (''specify other marking'')
  |} 
|-
|'''QUZ '''
|May I resume restricted working?<ref name="AP-1994-ch14"/>
|Distress phase still in force; restricted working may be resumed.<ref name="AP-1994-ch14"/> 
|}

===Amateur radio===
Amateur radio has adapted two different sets of Q-codes for use in amateur communications. The first set comes from the ITU civil series QRA through QUZ. Most of the meanings are identical to the ITU definitions, however, they must be looked at in the context of amateur communications. For example, QSJ? asks what the charges are for sending the telegraph. Since by regulation amateur communications are without charge, this Q-code couldn't make sense.

The second set is the set of [[QN Signals]], used only in ARRL [[National Traffic System|NTS]] nets. These operating signals generally have no equivalent in the ACP 131 publication or ITU publications, and are specifically defined only for use in ARRL NTS nets. They are not used in casual amateur radio communications.<ref>{{cite web |title=Operating Signals |date=12 December 2014 |publisher=[[American Radio Relay League|ARRL]] [[National Traffic System]] (NTS) |url=https://wb8ylo.wordpress.com/2014/12/11/operating-signals/ |access-date=30 March 2015 |url-status=dead |archive-date=2 April 2015 |archive-url=https://web.archive.org/web/20150402182452/https://wb8ylo.wordpress.com/2014/12/11/operating-signals/ }}</ref><ref>{{cite web |title=FSD-218 – Field Service Form: Instructions for NTS radiogram messages |url=http://www.arrl.org/files/file/Public%2520Service/fsd218.pdf}}</ref>

Selected Q-codes were soon adopted by [[amateur radio operator]]s. In December 1915, the [[American Radio Relay League]] began publication of a magazine titled ''[[QST]]'', named after the Q-code for "General call to all stations". In amateur radio, the Q-codes were originally used in Morse code transmissions to shorten lengthy phrases and were followed by a Morse code question mark ({{morse|dot|dot|dash|dash|dot|dot}}) if the phrase was a question.

Q-codes are commonly used in voice communications as shorthand nouns, verbs, and adjectives making up phrases. For example, an amateur radio operator will complain about QRM (man-made interference), or tell another operator that there is "QSB on the signal" (fading); "to QSY" is to change your operating frequency, or to break in on a conversation QSK is often used even on VHF and UHF frequencies. (See also [[Q code#Informal usage|Informal usage]], below.)

====Q-codes as adapted for use in amateur radio====
{{anchor | amateur_radio }}
{| class="wikitable" summary="Most common Q-codes used in the amateur radio service"
|-
! Code !! Question !! Answer or statement
|-
| QRA || What is the name (or call sign) of your station? || The name (or call sign) of my station is ____ 
|-
| QRG || Will you tell me my exact frequency (or that of ____)? || Your exact frequency (or that of ____ ) is ____ kHz (or MHz).
|-
| QRH || Does my frequency vary? || Your frequency varies. 
|-
| QRI || How is the tone of my transmission? || The tone of your transmission is (1. Good; 2. Variable; 3. Bad)
|-
| QRJ || How many voice contacts do you want to make? || I want to make ____ voice contacts.
|-
| QRK || What is the readability of my signals (or those of ____)?  || The readability of your signals (or those of ____) is ____ (1 to 5).
|-
| QRL || Are you busy? || I am busy (in contact with ____ ). Please do not interfere.
|-
| QRM || Do you have interference? || I have interference.
|-
| QRN || Are you troubled by static? || I am troubled by static.
|-
| QRO || Shall I increase power? || Increase power.
|-
| [[QRP operation|QRP]]|| Shall I decrease power? || Decrease power.
|-
| QRQ || Shall I send faster?  || Send faster (____ {{sc|wpm}}).
|-
| QRS || Shall I send more slowly?  || Send more slowly (____ {{sc|wpm}}).
|-
| QRT || Shall I stop sending?  || Stop sending.<ref>{{Cite web |date= |title=Morsum Magnificat Q & Z Codebook for the Morse-Telegraphy |url=http://www.n7cfo.com/tgph/Dwnlds/mm/MMs/Q&Z.pdf |access-date=20 October 2024}}</ref>
''Often heard colloquially as:''
I am suspending operation / shutting off the radio.
|-
| QRU || Have you anything for me?  || I have ____ messages for you.
|-
| QRV || Are you ready?  || I am ready.
|-
| QRW || Shall I inform ____ that you are calling (him) on ____ kHz (or MHz)? || Please inform ____ that I am calling (him) on ____ kHz (or MHz).
|-
| QRX || Shall I standby? / When will you call me again? || Please standby / I will call you again at ____ (hours) on ____ kHz (or MHz) 
|-
| QRZ || Who is calling me?  || You are being called by ____ on ____ kHz (or MHz)
|-
| QSA || What is the strength of my signals (or those of ____ )?  || The strength of your signals (or those of ____) is ____ (1 to 5).
|-
| QSB || Are my signals fading? || Your signals are fading.
|-
| QSD || Is my keying defective? || Your keying is defective.
|-
| QSG || Shall I send ____ telegrams (messages) at a time? || Send ____ telegrams (messages) at a time. 
|-
| [[QSK operation (full break-in)|QSK]]|| Can you hear me between your signals?  || I can hear you between my signals.
|-
| [[QSL card|QSL]]|| Can you acknowledge receipt?  || I will acknowledge receipt.
|-
| QSM || Shall I repeat the last telegram (message) which I sent you, or some previous telegram (message)?  || Repeat the last telegram (message) which you sent me (or telegram(s) / message(s) numbers(s) ____ ).
|-
| QSN || Did you hear me (or ____ (call sign)) on ____ kHz (or MHz)?  || I did hear you (or ____ (call sign)) on ____ kHz (or MHz).
|-
| [[Contact (amateur radio)|QSO]]|| Can you communicate with ____ direct or by relay?  || I can communicate with ____ direct (or by relay through ____ ).
|-
| QSP || Will you relay a message to ____ ? || I will relay a message to ____ .
|-
| QSR || Do you want me to repeat my call? || Please repeat your call; I did not hear you.
|-
| QSS || What working frequency will you use? || I will use the working frequency ____ kHz (or MHz).
|-
| QST || Should I repeat the prior message to all amateurs I contact? || Here follows a broadcast message to all amateurs.
|-
| QSU || Shall I send or reply on this frequency (or on ____ kHz (or MHz))? || Send or reply on this frequency (or on ____ kHz (or MHz)).
|-
| QSW || Will you send on this frequency (or on ____ kHz (or MHz))? || I am going to send on this frequency (or on ____ kHz (or MHz)). 
|-
| QSX || Will you listen to ____ (call sign(s) on ____ kHz (or MHz))?  || I am listening to ____ (call sign(s) on ____ kHz (or MHz)) 
|-
| QSY || Shall I change to transmission on another frequency?  || Change to transmission on another frequency (or on ____ kHz (or MHz)).
|-
| QSZ || Shall I send each word or group more than once? || Send each word or group twice (or ____ times). 
|-
| QTA || Shall I cancel telegram (message) number ____ as if it had not been sent?  || Cancel telegram (message) number ____ as if it had not been sent.
|-
| QTC || How many telegrams (messages) have you to send?  || I have ____ telegrams (messages) for you (or for ____ ).
|-
| QTH || What is your position in latitude and longitude? (or according to any other indication) || My position is ____ latitude ____ longitude.
|-
| QTR || What is the correct time? || The correct time is ____ hours [[UTC]].
|-
| QTU || At what times are you operating? || I am operating from ____ to ____ hours.
|-
| QTX || Will you keep your station open for further communication with me until further notice (or until ____ hours)? || I will keep my station open for further communication with you until further notice (or until ____ hours). 
|-
| QUA || Have you news of ____ (call sign)? || Here is news of ____ (call sign). 
|-
| QUC || What is the number (or other indication) of the last message you received from me (or from ____ (call sign))? || The number (or other indication) of the last message I received from you (or from ____ (call sign)) is ____.
|-
| QUD || Have you received the urgency signal sent by ____ (call sign of mobile station)? || I have received the urgency signal sent by ____ (call sign of mobile station) at ____ hours.
|-
| QUE || Can you speak in ____ (language) – with interpreter if necessary – if so, on what frequencies? || I can speak in ____ (language) on ____ kHz (or MHz).
|-
| QUF || Have you received the distress signal sent by ____ (call sign of mobile station)? || I have received the distress signal sent by ____ (call sign of mobile station) at ____ hours. 
|}

====Notes for response to radiotelegraph Q-codes====
Responses to a radiotelegraph Q-code query or a Q-code assertion may vary depending upon the code. For Q-code assertions or queries which only need to be acknowledged as received, the usual practice is to respond with the letter "R" for "Roger" which means "Received correctly". Sending an "R" merely means the code has been correctly received and does not necessarily mean that the receiving operator has taken any other action.

For Q-code queries that need to be answered in the affirmative, the usual practice is to respond with the letter "C" (Sounds like the Spanish word "Si"). For Q-code queries that need to be answered in the negative, the usual practice it to respond with the letter "N" for "no". For those Q-code assertions that merely need to be acknowledged as understood, the usual practice is to respond with the [[Prosigns for Morse code|prosign]] {{overline|SN}} (or {{overline|VE}}) which means "understood". On telegraph cable networks "KK" was often used at the end of a reply to a Q-code to mean "OK" or "Acknowledged". This practice predates amateur radio as telegraph operators in the late 19th century are known to have used it.

====Informal usage====
[[Image:International Morse Code.svg|right|thumb|315px|Chart of the [[Morse code]] letters and numerals.<ref name='itu-r'>{{cite web |url=http://www.itu.int/rec/R-REC-M.1677-1-200910-I/ |title=International Morse code Recommendation ITU-R M.1677-1  |date=October 2009 |work=itu.int |publisher=International Telecommunication Union |access-date=23 December 2011}}</ref>]]

'''QAC''' - Taken from the Articles of Association of the South Hampshire International Telegraphy Society, para 9: "...and amongst themselves they shall promote the Use of the Code QAC, which shall be taken as implying "All Compliments" and shall include:- VY 73 73 OM CUL BCNU & mni tnx fer nice/FB/rotten QSO GL GB hpe cuagn wid gud/btr/wrse condx mri Xms Hpi Nw Yr mni hpi rtrns gtgs fer Rosh Hoshanah/Id el Fitr/May Day/Tksgvg 88 to XYL/YL/Widow Ciao Cheerio & gud/FB/best DX or any Part or Parts thereof in any Permutation or Combination.<ref>{{Cite web |title=G2JL Callsign Page |url=https://www.qrz.com/db/G2JL |access-date=2024-03-02 |website=QRZ Callsign Database |language=en-US}}</ref>

'''QLF''' – "Are you sending with your left foot? Try sending with your left foot!"  A humorously derogatory comment about the quality of a person's sending.<ref>{{cite web |author=The Free Dictionary |title=Definition of QLF |url=http://acronyms.thefreedictionary.com/QLF |publisher=The Free Dictionary |access-date=1 July 2016}}</ref><ref>{{cite web |title=Capitalizing on your Capital Project |url=http://www.arrl.org/news/capitalizing-on-your-capital-project |website=ARRL.org |publisher=American Radio Relay League |access-date=1 July 2016}}</ref>

'''QNB''' – QNB? “How many buttons on your radio?” “QNB 100/5” Means there are 100 and I know what 5 of them do.

'''[[QSK operation (full break-in)|QSK]]''' – "I can hear you during my transmission" – refers to a particular mode of Morse code operating often called [[QSK operation (full break-in)]] in which the receiver is quickly enabled during the spaces between the dits and dahs, which allows another operator to interrupt transmissions. Many modern [[transceivers]] incorporate this function, sometimes referred to as ''full break-in'' as against ''semi-break-in'' in which there is a short delay before the transceiver goes to receive.<ref name="CIOS">{{cite web |url=http://jcs.dtic.mil/j6/cceb/acps/acp131/ACP131F.pdf |title=Communications Instructions Operating Signals |date=April 2006 |publisher=[[Combined Communications Electronics Board]] |access-date=2014-05-16  |url-status=dead |archive-url=https://web.archive.org/web/20120906015123/http://jcs.dtic.mil/j6/cceb/acps/acp131/ACP131F.pdf |archive-date=September 6, 2012}}</ref>

'''QSY''' – "Change to transmission on another frequency"; colloquially, "move [=change address]". E.g., "When did [http://www.qsl.net/gm3zdh/coast/uk/gka/closedown/final-msg.htm GKB] QSY from Northolt to Portishead?"<ref>{{cite web |url=https://groups.google.com/d/msg/uk.radio.amateur/5LRgiCMoNcI/kObVDDoEi9gJ |format=Post |title=The uk.radio.amateur newsgroup |date=2010-08-21 |access-date=2013-08-04}}</ref>

'''QTH''' – "My location is&nbsp;____"; colloquially in voice or writing, "location". E.g., "The OCF ''[antenna type]'' is an interesting build but at my QTH a disappointing performer."<ref>{{cite web |url=http://www.amateur-radio-wiki.net/index.php?title=Has_anyone_used_a_tuner_with_an_Off_Centre_Fed_Dipole%3F_How_well_did_it_work%3F |title=Has anyone used a tuner with an Off Centre Fed Dipole? How well did it work? |website=Amateur Radio Wiki |access-date=2013-08-04}}</ref>

'''QTHR''' – "At the registered location&nbsp;____"; chiefly British use. Historically, the location in the printed Callbook; modernly, "as given in online government records for my callsign". E.g., "You can contact me QTHR".<ref>{{cite web |url=https://www.ukrepeater.net/list1q.php |title=List of repeaters in the UK sorted by QTHR |access-date=2016-06-01}}</ref>

'''QBL''' – “Quit Bein' a Lid” QBL is used among amateur radio operators to indicate humour in their CW transmission. While QBL is generally used by a small subsection of operators who can properly decode, it is available to anyone.

====German use during World War II====
During World War II, according to [[Bletchley Park]]’s ''General Report on Tunny,''<ref>{{cite web |url=http://www.alanturing.net/turing_archive/archive/t/t01/TR01-016.html |title=TR01-016 |website=www.alanturing.net}}</ref> German radio teleprinter networks used Q-codes to establish and maintain circuit connections.

In particular: '''QKP''' [ought to be 'QEP', not 'QKP' - the print in the source document isn't very clear] was to indicate the [[Lorenz cipher]] machine setting for each message and, '''QZZ''' to indicate that the daily key change was about to take place at the sender's station.

<!-- FIXED REFERENCES (define these before <references /> or first usage) -->
<ref name="AP-1994-ch13">International Telecommunication Union. "ITU Radio Regulations 1994, Appendix 13". Geneva: ITU, 1994.</ref>
<ref name="AP-1994-ch14">International Telecommunication Union. "ITU Radio Regulations 1994, Appendix 14". Geneva: ITU, 1994.</ref>

<ref name="AP-1994-ch1">International Telecommunication Union. "ITU Radio Regulations 1994, Appendix 1". Geneva: ITU, 1994.</ref>

<!-- REFERENCES SECTION -->
==References==
<references />

==Notes==
<references group="lower-alpha" />

== See also ==

* {{annotated link|ACP-131}}
* {{annotated link|Amateur radio}}
* {{annotated link|Brevity code}}
* {{annotated link|International Code of Signals}}
* {{annotated link|International maritime signal flags}}
* {{annotated link|Morse code}}
* {{annotated link|NOTAM Code}}
* {{annotated link|Prosigns for Morse code}}
* {{annotated link|QRA locator}}
* {{annotated link|QSK operation (full break-in)}}
* {{annotated link|Ten-code}}
* {{annotated link|Z code}}

{{DEFAULTSORT:Q Code}}
[[index.php?title=Category:Amateur radio]]
[[index.php?title=Category:Encodings]]
[[index.php?title=Category:Morse code]]
[[index.php?title=Category:Operating signals]]
[[index.php?title=Category:Telecommunications-related introductions in 1909]]



==Notes==
<references group="lower-alpha" />

<!-- Ensure that named references used in the article are defined here -->
<ref name="AP-1994-ch13">International Telecommunication Union. "ITU Radio Regulations 1994, Appendix 13". Geneva: ITU, 1994.</ref>
<ref name="AP-1994-ch14">International Telecommunication Union. "ITU Radio Regulations 1994, Appendix 14". Geneva: ITU, 1994.</ref>

== See also ==

* {{annotated link|ACP-131}}
* {{annotated link|Amateur radio}}
* {{annotated link|Brevity code}}
* {{annotated link|International Code of Signals}}
* {{annotated link|International maritime signal flags}}
* {{annotated link|Morse code}}
* {{annotated link|NOTAM Code}}
* {{annotated link|Prosigns for Morse code}}
* {{annotated link|QRA locator}}
* {{annotated link|QSK operation (full break-in)}}
* {{annotated link|Ten-code}}
* {{annotated link|Z code}}

{{DEFAULTSORT:Q Code}}
[[index.php?title=Category:Amateur radio]]
[[index.php?title=Category:Encodings]]
[[index.php?title=Category:Morse code]]
[[index.php?title=Category:Operating signals]]
[[index.php?title=Category:Telecommunications-related introductions in 1909]]